Measurement device, measurement method, and measurement program

Abstract

A measuring device capable of measuring the physical quantity of an object to be measured at a relatively low cost without reducing work efficiency is provided. [Solution] A measuring device 1 that measures a predetermined physical quantity of a measurable object O, comprising a contact portion 12 configured to be able to come into contact with the measurable object O, a position detection unit 20 that detects the contact portion position, which is the position of the contact portion 12, and a control unit 30 that has a calculation unit 31 that measures the physical quantity of the measurable object O based on an external force F generated in the contact portion 12, which is calculated based on the difference between a set target position Xd and the contact portion position X.

Description

[Technical Field]

[0001] The present invention relates to a measurement device, a measurement method, and a measurement program. [Background technology]

[0002] Conventionally, dedicated measuring instruments have been used to measure the physical quantities of measurement objects, such as mass meters such as electronic balances for measuring the mass of measurement objects (see, for example, Patent Document 1), and laser measuring instruments for measuring the dimensions of measurement objects. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 55-116223 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in these cases, it is necessary to move the object to be measured to a dedicated measuring instrument using a manipulator, conveyor, or the like, and operate the dedicated measuring instrument to measure a predetermined physical quantity of the object to be measured. Furthermore, after the measurement is completed, it is necessary to move the object to be measured again using a manipulator, or the like, to the location where the next work process will be carried out. Therefore, there is a problem in that it takes time and effort to move and measure the object to be measured, which may reduce work efficiency.

[0005] In addition, dedicated measuring instruments such as mass meters and laser measuring devices are relatively expensive, and there has been a demand for low-cost measuring devices that can measure physical quantities such as the mass and size of objects being measured.

[0006] Therefore, the present invention has been made in consideration of the above circumstances, and has an object to provide a measurement device that can measure the physical quantity of a measurement object at a relatively low cost without reducing work efficiency. It also has an object to provide a measurement method for performing such measurements. It is still another object to provide a measurement program that can be executed by a CPU to measure the physical quantity of a measurement object. [Means for solving the problem]

[0007] The measuring device of the present invention is a measuring device that measures the physical quantity of a measured object, and is characterized by comprising: a contact portion configured to be able to come into contact with the measured object; a position detection portion that detects the contact portion position, which is the position of the contact portion; and a control portion having a calculation portion that measures the physical quantity of the measured object based on an external force generated in the contact portion, which is calculated based on the difference between a set target position and the contact portion position.

[0008] The measurement method of the present invention is a measurement method for measuring a physical quantity of a measured object, and is characterized by including a contact part position detection step for detecting the position of a contact part configured to be able to come into contact with the measured object, and a calculation step for measuring the physical quantity of the measured object based on an external force generated in the contact part, which is calculated based on the difference between a set target position and the position of the contact part.

[0009] The measurement program of the present invention is a measurement program for measuring a physical quantity of a measured object, and is characterized in that it causes a CPU to execute a contact part position input process for inputting the position of a contact part configured to be able to come into contact with the measured object, and a calculation process for measuring a predetermined physical quantity based on an external force generated in the contact part, which is calculated based on the difference between a set target position and the position of the contact part, thereby measuring the physical quantity of the measured object.

[0010] According to the measurement device, measurement method, and measurement program of the present invention, the control unit has a calculation unit that measures the physical quantity of the object to be measured based on the external force generated at the contact portion, which is calculated based on the difference between the set target position and the contact portion position, so that the physical quantity of the object to be measured can be measured simply by detecting the set target position and the contact portion position. Therefore, since a dedicated measuring instrument is not required, there is no need to move the object to be measured to the dedicated measuring instrument using a manipulator or the like, and work efficiency can be improved.

[0011] According to the measurement device, measurement method, and measurement program of the present invention, since a dedicated measuring instrument is not required as described above, it becomes possible to measure physical quantities such as the mass and size of an object at low cost. [Brief explanation of the drawings]

[0012] [Figure 1] 1 is a block diagram shown for explaining a measurement device 1 according to a first embodiment. [Figure 2] FIG. 1 is a block diagram illustrating a computer 100 according to a first embodiment. [Figure 3] FIG. 2 is a schematic diagram for explaining impedance control in the first embodiment. [Figure 4] 1 is a schematic diagram shown for explaining a measuring device 1 (mass measuring device) according to a first embodiment and a first modified example. [Figure 5] 1 is a flowchart shown to explain a measurement method (mass measurement method) according to the first embodiment. [Figure 6] FIG. 10 is a schematic diagram shown for explaining a measuring device (dimension measuring device) according to a second embodiment. [Figure 7] FIG. 10 is a schematic diagram shown for explaining a measuring device (dimension measuring device) according to Modification 2. [Figure 8] 10 is a flowchart shown to explain a measurement method (dimension measurement method) according to the second embodiment. [Figure 9] FIG. 10 is a schematic diagram for explaining a measuring device (hardness measuring device) according to a third embodiment. [Figure 10]FIG. 10 is a schematic diagram for explaining a measuring device (hardness measuring device) according to Modification 3. [Figure 11] FIG. 10 is a schematic diagram shown for explaining a measurement device (shape measurement device) according to a fourth modification. DETAILED DESCRIPTION OF THE INVENTION

[0013] The measurement device, measurement method, and measurement program of the present invention will be described below based on the embodiments shown in the drawings. Note that the embodiments described below do not limit the invention according to the claims. Furthermore, not all of the elements and combinations thereof described in the embodiments are necessarily essential to the solution of the present invention.

[0014] [Embodiment 1] 1. Measurement equipment using an impedance control model The measurement device 1 according to the first embodiment measures a physical quantity of a measurement target object based on an external force generated at a contact part, which is calculated based on the difference between a set target position and the contact part position. An impedance control model is used as a method for calculating the external force.

[0015] First, we will explain impedance control. Impedance control is a force control method that controls the driving force of a robot's hand (including the contact part) using the position of the contact part and mechanical impedance (inertia, viscosity, rigidity, etc.).

[0016] As shown in Fig. 3, impedance control models the external force (external force vector, hereinafter simply referred to as external force) generated at the contact point using the following equation (1) to control the position and force of the contact point. In equation (1), M represents the inertia matrix, D represents the viscosity matrix, K represents the stiffness matrix, X represents the position and posture vector of the contact point, Xd represents the target position and posture vector, and F represents the external force vector generated at the contact point. The first term on the left side of equation (1) is the inertia term, the second term is the viscosity term, and the third term is the stiffness term.

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[0017] As is clear from the above equation (1), in impedance control, the external force can be calculated from the difference between the set target position and the contact position and the impedance value (inertia matrix M, viscosity matrix D, and stiffness matrix K).

[0018] 2. Configuration of the measuring device 1 according to the first embodiment Next, a description will be given of the configuration of the measurement device 1 according to embodiment 1. The measurement device 1 according to embodiment 1 is a measurement device that measures the mass of a measurement object based on the relationship between an external force generated at a contact portion and gravity applied to the measurement object.

[0019] 1, the measurement device 1 according to the first embodiment includes a manipulator 10, a position detection unit 20, a control unit 30, a target position information generation unit 40, an output unit 50, and a storage unit 60. In the first embodiment, a measurement object O is placed on a contact unit 12 of the manipulator 10, and the mass of the measurement object O is measured.

[0020] The manipulator 10 has a movable part 11 and a contact part 12 provided at the tip of the movable part 11 .

[0021] The movable unit 11 is configured to be able to move the contact unit 12. In the first embodiment, the movable unit 11 is a robot arm extending from a base (base) 14, as shown in FIG. 3. The movable unit 11 has a first link L1, a second link L2, and a third link L3, a first joint 15 between the base 14 and the first link L1, a second joint 16 between the first link L1 and the second link L2, and a third joint 17 between the second link L2 and the third link L3. In the first embodiment, the movable unit 11 is a multi-axis controlled robot arm having three joints, but it may be a multi-axis controlled robot arm having two or four or more joints, or a single-axis controlled robot arm. Furthermore, a configuration other than a robot arm may also be used. A movable base may be used as the base 14.

[0022] Each joint is provided with a motor M1 to M3, and the position of the contact part 12 can be moved by rotating the motors M1 to M3 in response to a drive signal that controls the rotational torque of the motor from the control unit 30.

[0023] The contact unit 12 is a hand provided at the tip of the movable unit 11, and is configured to be able to come into contact with the measurement object O. The contact unit 12 may be configured to be able to place the measurement object O on it, or may be configured to be able to grip the measurement object O.

[0024] The position detection unit 20 detects the contact portion position, which is the position of the contact portion 12. Specifically, an encoder is provided at each of the first joint portion 15, the second joint portion 16, and the third joint portion 17 of the movable portion 11, and each encoder detects the rotation phase angle of the rotation shaft of the motors M1 to M3 and outputs the detected rotation phase angle as contact portion position information to the control unit 30. Note that the contact portion position information may include appropriate information such as the rotation phase angle and position, as well as the rotation speed and rotation acceleration of the motor.

[0025] The control unit 30 measures the mass of the measurement object based on the external force generated at the contact unit 12, which is calculated based on the difference between the set target position and the contact unit position. The control unit 30 also performs impedance control on the movable unit 11. Furthermore, the control unit 30 calculates the position of the contact unit 12 based on the rotation phase angles of the rotation shafts of the motors M1 to M3 and the lengths of the links L1 to L3 that have been measured in advance.

[0026] The control unit 30 has a calculation unit 31 and a drive signal generation unit 32. The control unit 30 and a target position information generation unit 40 (described later) are implemented by executing a program on the CPU of a computer 100 (described later), but separate computers may be used for each, or a configuration other than a program may be used using a logic circuit or the like.

[0027] The calculation unit 31 measures the mass of the measurement object O based on the external force F generated on the contact unit 12, which is calculated based on the difference between the set target position and the contact unit position. Specifically, (1) contact unit position information regarding the first contact unit position Xini when the measurement object O is not placed is input, and the external force F1 is calculated, (2) next, the measurement object O is placed on the contact unit 12, and contact unit position information regarding the second contact unit position Xfin is input, and the external force F2 is calculated, and (3) the mass m of the measurement object O is calculated because the difference between the external force F2 and the external force F1 is equal to gravity (= mass × gravitational acceleration).

[0028] The drive signal generation unit 32 outputs a drive signal that controls the rotation torque of the motors M1 to M3 provided on each axis of the movable unit 11, based on the target position set by the target position information generation unit 40 and the external force calculated by the calculation unit 31. The drive signal generation unit 32 may also output a signal that causes the contact unit 12 to perform an operation such as gripping the measurement object O.

[0029] The target position information generating unit 40 sets a target position Xd and outputs it to the calculating unit 31. In the first embodiment, the manipulator 10 is controlled so that the contact portion 12 moves toward the set target position Xd, but the target position Xd is set so that the target position Xd is fixed (so that the target position Xd does not move) at least from the timing when the first contact portion position Xini is detected to the timing when the second contact portion position Xfin is detected.

[0030] 3. Configuration of the Computer 100 in the First Embodiment Next, the computer 100 in the first embodiment will be described. The computer 100 realizes the control unit 30 and the target position information generation unit 40 by causing the CPU 105 to execute a program. As shown in FIG. 2, the computer 100 has a transmission unit 101, a reception unit 102, a BUS 103, and the CPU 105. The computer 100 is also connected to an output unit 50, a storage unit 60, and an input unit 70 via the BUS 103. Note that a memory that stores the target position and the contact position for each predetermined time may be provided separately from the storage unit 60, which will be described later.

[0031] The transmitting unit 101 outputs a drive signal to the manipulator 10. The receiving unit 102 receives contact part position information relating to the contact part position detected by the position detecting unit 20. The output unit 50 displays the mass calculated by the calculation unit 31. The storage unit 60 stores the model formula (1) of impedance control, gravity coefficients, impedance values ​​(inertia matrix M, viscosity matrix D, and stiffness matrix K), etc. It also temporarily stores contact part position information, target position information, etc.

[0032] 4. Measurement Method According to Embodiment 1 Next, a measurement method according to the first embodiment will be described with reference to Fig. 4 and Fig. 5. The measurement method according to the first embodiment is a measurement method for measuring the mass of a measurement object O. As shown in Fig. 5, the measurement method according to the first embodiment includes a target position setting step S11, a first contact portion position detection step S12, a placement step S13, a second contact portion position detection step S14, and a calculation step S15.

[0033] (1) Target position setting step S11 First, the control unit 30 sets a target position Xd. In this case, the target position Xd may be set to move over time, but the target position Xd is fixed at least from the first contact position Xini detection step to the second contact position detection step. In the first embodiment, the contact unit 12 is moved toward the target position Xd, and the first contact position Xini detection step S12 is performed when the contact unit 12 reaches the target position Xd.

[0034] (2) First contact position Xini detection step S12 Next, a first contact position Xini, which is the position of the contact portion 12 before the measurement object O is placed on the contact portion 12, is detected (see FIG. 4(a)). Information about the detected first contact position Xini is output to the control unit 30, which calculates a first external force F1=K(Xd-Xini) based on the difference between the target position Xd and the first contact position Xini. Note that the external force F1 is calculated from equation (1) for impedance control, but since it is unlikely that the measurement object O will move at high speed or undergo sudden acceleration or deceleration, for simplicity, the first and second terms of equation (1) are set to zero, and the third term (rigidity term) is calculated as the external force F1 (the same applies to the second external force F2 described below). In the first embodiment, the first contact position Xini detection step is performed when the contact portion 12 reaches the target position Xd. At this time, the measurement object O has not yet been placed, so the first contact position Xini = the target position Xd. Therefore, the difference at the first contact position Xini (the difference between the position of the contact portion and the target position) is ideally zero, and the external force F1 generated on the contact portion 12 at the first contact position Xini is also zero.

[0035] (3) Placement step S13 Next, the measurement object O is placed on the contact portion 12. At this time, the weight (gravity) of the measurement object O causes the contact portion 12 to move downward. As a result, the difference between the target position Xd and the position of the contact portion 12 increases, and the external force generated on the contact portion 12 increases, so that the contact portion 12 balances at a predetermined position (see FIG. 4(b)).

[0036] (4) Second contact position detection step S14 Next, a second contact position Xfin is detected, which is the position of the contact portion 12 after the measurement object O is placed on the contact portion 12. Information about the detected second contact position Xfin is output to the control unit 30 as second contact position information, and a second external force F2=K(Xd-Xfin) is calculated based on the difference between the target position Xd and the second contact position Xfin.

[0037] (5) Calculation process S15 Next, the mass m of the measurement object O is measured based on the relationship between the first external force F1, the second external force F2, and the gravity applied to the measurement object O. First, the difference between the first external force F1 and the second external force F2 is calculated to calculate K(Xini - Xfin). Meanwhile, gravity can be expressed in mg when the gravitational acceleration is g. Therefore, the following equation (2) is satisfied due to the balance of forces.

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[0038] The mass m can be calculated (measured) by solving equation (2). The measurement result can be displayed using the output unit 50.

[0039] 5. Measurement program according to embodiment 1 Next, a description will be given of the measurement program according to embodiment 1. The measurement program according to embodiment 1 causes the CPU to execute first contact position information input processing, second contact position information input processing, and calculation processing.

[0040] First, the control unit 30 sets the target position Xd. The set target position Xd is stored in the storage unit 60. At this time, the target position Xd is set to a fixed position at least from before the measurement object O is placed on the contact unit 12 until after the measurement object O is placed on the contact unit 12.

[0041] (1) First contact position information input process First, first contact portion position information regarding the first contact portion position Xini, which is the position of the contact portion 12 before the measurement object O is placed on the contact portion 12, is input. Specifically, information regarding the rotational phase angles of the rotation shafts of the motors M1 to M3 output from the encoders in the position detection unit 20 is received by the receiving unit 102 and input to the CPU 105. The CPU 105 reads the dimensions of each of the link portions L1 to L3 stored in the storage unit 60 and performs a process of calculating the first contact portion position Xini of the contact portion 12. In addition, a first external force F1=K(Xd-Xini) is calculated based on the difference between the target position Xd and the first contact portion position Xini. The calculated first contact portion position Xini and first external force F1 are stored in the storage unit 60. The length of each link, the impedance control model equation (1), and the impedance values ​​(inertia matrix M, viscosity matrix D, and stiffness matrix K) are stored in the memory unit 60, and the CPU 105 reads this information to calculate the first contact position Xini and the first external force F1.

[0042] (2) Second contact position information input process Next, second contact position information regarding a second contact position Xfin, which is the position of the contact portion 12 after the measurement object O is placed on the contact portion 12, is input. Also, a second external force F2=K(Xd-Xfin) is calculated based on the difference between the target position Xd and the second contact position Xfin. The calculated second contact position Xfin and second external force F2 are stored in the memory unit 60.

[0043] (3) Calculation processing Next, the CPU 105 calculates the mass m of the measurement object O based on the relationship between the first external force F1, the second external force F2, and the gravity applied to the measurement object O. Specifically, the CPU 105 reads the impedance control model equation (1), the gravity-related coefficients, and the impedance values ​​(inertia matrix M, viscosity matrix D, and stiffness matrix K) from the storage unit 60, and calculates the mass of the measurement object O from the above equation (2). The calculated value of mass m is output via the output unit 50.

[0044] 6. Effects of the measurement device 1, measurement method, and measurement program according to the first embodiment According to the measuring device 1, measuring method, and measuring program of the first embodiment, the control unit 30 has a calculation unit 31 that measures a predetermined physical quantity based on the external force F generated on the contact unit 12, which is calculated based on the difference between the set target position Xd and the contact unit position, so that the predetermined physical quantity can be calculated simply by detecting the set target position Xd and the contact unit position. Therefore, a dedicated measuring instrument is not required, and there is no need to move the object to be measured to the dedicated measuring instrument using a manipulator or the like, thereby improving work efficiency.

[0045] According to the measuring device 1, measuring method, and measuring program of embodiment 1, as described above, mass meters and dedicated measuring instruments are not required, and therefore it is possible to measure physical quantities such as the mass and size of an object at low cost.

[0046] According to the measuring device 1, the measuring method, and the measuring program of the first embodiment, a predetermined physical quantity can be calculated simply by detecting the target position and the contact position set as described above, and therefore, mass can be easily measured for various applications.

[0047] Furthermore, according to the measuring device 1 of embodiment 1, the calculation unit 31 measures the mass of the object to be measured O based on the relationship between the external force F and the gravity applied to the object to be measured O, so that the mass can be easily measured by simply detecting the difference (and the impedance value) between the target position and the contact position.

[0048] Furthermore, according to the measuring device 1 of embodiment 1, the external force is calculated based on the following formula (1), so that the external force can be calculated simply by detecting the set target position Xd and the contact position, and the mass of the measured object O can be measured.

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[0049] Furthermore, the measuring device 1, measuring method, and measuring program according to the first embodiment further include a robot arm that controls the contact portion 12, and the control unit 30 is configured to be able to move the contact portion 12 toward the target position Xd by controlling the rotational torque of the motors M1 to M3 provided on the axis of the robot arm, thereby increasing the degree of freedom of movement such as the position, orientation, and rotation of the contact portion 12. Furthermore, the position of the contact portion 12, and therefore the position of the object to be measured, can be easily measured based on the rotational phase angle of an encoder attached to the joint of the robot arm.

[0050] Furthermore, according to the measuring device 1 of the first embodiment, the control unit 30 performs impedance control on the movable unit 11 and measures the physical quantity of the measurement object O, so that the contact unit 12 can perform both the role of a normal manipulator that performs a predetermined task (for example, gripping, drilling, etc.) and the role of a measuring device. Therefore, the contact unit 12 can measure the predetermined physical quantity of the measurement object O before and after the predetermined task or while the contact unit 12 is moving, and the work efficiency can be further improved.

[0051] [Variation 1] The measurement device according to Modification 1 basically has the same configuration as the measurement device 1 according to Embodiment 1, but differs from the measurement device 1 according to Embodiment 1 in that it uses a single-axis manipulator instead of a multi-axis one. That is, as shown in Fig. 4(c), the measurement device according to Modification 1 has a movable part 11a in which a link part L1 extends linearly from a base part 14, and a contact part 12 provided at the tip of the movable part 11a.

[0052] In the first modification, a first contact position Xini, which is the position of the contact portion 12 before the measurement object O is placed on the contact portion 12, is detected, and an external force F1 is calculated. In the first modification, a rotation angle θd is used as the target position. When the measurement object O is placed, the movable portion 11a rotates from the central base portion 14. Then, a second contact position Xfin, which is the position of the contact portion 12 after placement, is detected, and an external force F2 is calculated (see FIG. 4(d)). The second contact position Xfin is calculated using the angle θ from the first contact position Xini and the link portion L1. The target position may also be set using the angle at the position of the contact portion 12 before the measurement object O is placed on the contact portion 12.

[0053] Then, the mass of the measurement object O is measured based on the relationship between the first external force F1, the second external force F2, and the gravity applied to the measurement object O.

[0054] As described above, the measurement device according to Modification 1 differs from the measurement device 1 according to Embodiment 1 in that it uses a single-axis manipulator instead of a multi-axis one, but like the measurement device 1 according to Embodiment 1, the control unit 30 has a calculation unit 31 that measures the physical quantity of the object to be measured based on the external force F generated at the contact unit 12, which is calculated based on the difference between the set target position Xd and the contact unit position, so that it is possible to calculate a predetermined physical quantity simply by detecting the set target position Xd and the contact unit position. Therefore, a dedicated measuring instrument is not required, and there is no need to move the object to be measured to the dedicated measuring instrument using a manipulator or the like, thereby improving work efficiency.

[0055] The measuring device according to variant 1 has the same configuration as the measuring device according to embodiment 1 except that it uses a single-axis manipulator instead of a multi-axis one, and therefore has the corresponding effects of the measuring device according to embodiment 1.

[0056] [Embodiment 2] The measuring device 2 according to the second embodiment basically has the same configuration as the measuring device 1 according to the first embodiment, but differs from the measuring device 1 according to the first embodiment in that it performs dimension measurement instead of mass measurement (see FIG. 6).

[0057] In the second embodiment, the control unit 30 moves the contact unit 12 toward a target position Xd that is set so that at least the contact unit 12 comes into contact with the measurement object O. In the second embodiment, the control unit 30 moves the target position Xd along the dashed arrow in Fig. 6, and moves the contact unit 12 toward the target position Xd. Then, the external force is calculated based on the difference between the contact unit position and the target position.

[0058] The calculation unit 31 calculates the external force based on the difference between the contact portion position and the target position, and measures the dimensions of the measurement object O based on a preset threshold and the external force. Before the contact portion 12 contacts the measurement object O, the difference between the contact portion position and the target position does not change significantly. However, when the contact portion 12 contacts the measurement object O (see the solid line in FIG. 6), the contact portion 12 cannot move any further, while the target position Xd continues to move. Therefore, the difference becomes larger, and the external force becomes stronger. Then, when it is determined that the external force exceeds the threshold, the position of the contact portion 12 is determined to be the outer edge of the measurement object O, and the dimensions of the measurement object O are measured.

[0059] <Measurement method according to embodiment 2> Next, a description will be given of a measurement method according to embodiment 2. The measurement method according to embodiment 2 is a measurement method for measuring the dimensions of a measurement object O. As shown in Fig. 8, the measurement method according to embodiment 2 includes a target position setting step S21, a contact portion position detection step S22, and calculation steps S23 to S26.

[0060] (1) Target position setting step S21 First, a target position Xd is set so that at least the contact portion 12 comes into contact with the measurement object O (see the dashed arrow in FIG. 6 and step S21 in FIG. 8). The target position Xd is set so that the measurement object O moves from above to below.

[0061] (2) Contact position detection step S22 Next, the contact portion 12 is moved from the contact portion position Xini toward the target position Xd to detect the contact portion position X, which is the position of the contact portion 12 (see step S22 in FIG. 8). In the second embodiment, the detected first contact portion position information is input to the control unit 30. Note that in the second embodiment, the contact portion 12 is moved from the position X=Xini above the measurement object O to the position X=Xfin below.

[0062] (3) Calculation process S23 Next, the control unit 30 detects a difference ΔX=X-Xd from the contact position X and the target position Xd (see step S23 in FIG. 8), and compares the external force calculated based on the contact position with a preset threshold. Then, the contact position when the external force exceeds the threshold is recognized as the position of the contact portion 12 being the outer edge of the measurement object O. Note that although the external force is compared with the threshold, since it is essentially only necessary to compare the difference ΔX, it is not necessary to calculate the external force itself, and it is only necessary to compare the difference ΔX with a set value Xset of the difference.

[0063] That is, the difference ΔX is compared with the set value Xset (see step S24 in FIG. 8), and if the difference ΔX>Xset (see the solid line in FIG. 6 and the contact portion position Xfin), the position of the contact portion 12 is recognized as the outer edge of the measurement object O, and the dimensions of the measurement object O are measured (see step S26 in FIG. 8). That is, the contact portion 12 cannot move any further, whereas the target position Xd continues to move, and the difference ΔX exceeds the set value Xset.

[0064] If ΔX≦Xset, the target position Xd is moved by ΔXd (see step S25 in FIG. 8), and the process returns to step S21. That is, if the contact portion 12 has not reached the measurement object O, the contact portion 12 also moves in accordance with the movement of the target position Xd, and therefore ΔX≦Xset is maintained.

[0065] In this way, the dimensions of the measurement object O can be measured.

[0066] <Measurement program according to the second embodiment> Next, a description will be given of a measurement program according to embodiment 2. The measurement program according to embodiment 2 causes a CPU to execute a target position setting process, a contact portion position information input process, and a calculation process, thereby measuring the dimensions of a measurement object O.

[0067] (1) Target position setting process First, the target position Xd is set so that at least the contact portion 12 comes into contact with the object O to be measured.

[0068] (2) Contact position information input processing Next, the contact portion 12 is moved toward the target position Xd, and contact portion position information regarding the contact portion position X, which is the position of the contact portion 12, is input.

[0069] (3) Calculation processing Next, the dimensions of the measurement object O are measured based on the external force calculated based on the contact position and a preset threshold value. Specifically, a difference ΔX = X - Xd is detected from the contact position X and the target position Xd, and the external force calculated based on the contact position is compared with a preset threshold value. Essentially, the difference ΔX is compared with a set difference value Xset. If ΔX > Xset, the position of the contact portion 12 is recognized as the outer edge of the measurement object O, and the dimensions of the measurement object O are calculated. If ΔX ≦ Xset, the target position Xd is moved by ΔXd, and the contact position is detected again.

[0070] As described above, the measuring device, measuring method, and program according to the second embodiment differ from the measuring device 1 according to the first embodiment in that they perform dimensional measurement instead of mass measurement, but like the measuring device 1, measuring method, and program according to the first embodiment, the control unit 30 has a calculation unit 31 that measures a predetermined physical quantity based on the external force F generated at the contact unit 12, which is calculated based on the difference between the set target position Xd and the contact unit position, and therefore the physical quantity of the measurement object can be calculated simply by detecting the set target position Xd and the contact unit position. Therefore, a dedicated measuring instrument is not required, and there is no need to move the measurement object O to the dedicated measuring instrument using a manipulator or the like, thereby improving work efficiency.

[0071] According to the measuring device of embodiment 2, dimension measurement can be performed simply by changing the control of the control unit without changing the device configuration from the measuring device 1 of embodiment 1. Therefore, mass measurement and dimension measurement can be easily switched between.

[0072] The measuring device, measuring method, and program according to the second embodiment have the same configuration as the measuring device, measuring method, and program according to the first embodiment, except that they perform dimension measurement instead of mass measurement, and therefore have the corresponding effects of the measuring device, measuring method, and program according to the first embodiment.

[0073] [Variation 2] The measurement device according to Modification 2 basically has the same configuration as the measurement device 1 according to Embodiment 1, but differs from the measurement device 2 according to Embodiment 2 in the configuration of the contact unit. That is, in the measurement device according to Modification 2, the contact unit 12b is a contact unit that is moved toward the measurement object from both sides in the horizontal direction, as shown in FIG. 7. For example, the contact unit 12b is a finger of the hand 18, and the dimensions of the measurement object O are detected by reducing the spacing between the contact units 12b. This makes it possible to measure the dimensions of the measurement object O when gripping the measurement object using the hand, for example.

[0074] As described above, the measuring device according to Modification 2 differs from the measuring device 2 according to Embodiment 2 in the configuration of the contact unit, but like the measuring device 2 according to Embodiment 2, the control unit 30 has a calculation unit 31 that measures a predetermined physical quantity based on the external force F generated on the contact unit 12, which is calculated based on the difference between the set target position Xd and the position of the contact unit, and therefore the physical quantity of the object to be measured can be calculated simply by detecting the set target position Xd and the position of the contact unit. Therefore, a dedicated measuring instrument is not required, and there is no need to move the object to be measured to the dedicated measuring instrument using a manipulator or the like, thereby improving work efficiency.

[0075] The measuring device according to the second modification has the same configuration as the measuring device according to the second embodiment except for the configuration of the contact portion, and therefore has the corresponding effects of the measuring device according to the second embodiment.

[0076] [Embodiment 3] The measuring device 3 of embodiment 3 basically has the same configuration as the measuring device 2 of embodiment 2, but differs from the measuring device 2 of embodiment 2 in that it performs hardness measurement instead of dimensional measurement (see Figure 9).

[0077] The control unit operates the contact portion 12 toward a target position (from position X1 to X2 in FIG. 9) that is set so that at least the contact portion 12 comes into contact with the measurement object O. At this time, for example, the target position is also set to move from Xd1 to Xd2.

[0078] In addition, the calculation unit 31 calculates the hardness of the measurement object O based on a first difference, which is the difference between the target position and position X1 when the contact portion 12 is in contact with the measurement object O (see position X1 in Figure 9), and a first external force generated in the contact portion 12 calculated based on the first difference, and a second difference, which is different from the first difference (position X2 in Figure 9, the target position is Xd2), and a second external force generated in the contact portion 12 calculated based on the second difference.

[0079] Specifically, the calculation unit 31 calculates the hardness by substituting the first difference, the first external force, the second difference, and the second external force into the following equation (3).

number

[0080] <Measurement method according to embodiment 3> Next, a measurement method according to embodiment 3 will be described. The measurement method according to embodiment 3 is a measurement method for measuring hardness as a predetermined physical quantity of a measurement object O. The measurement method according to embodiment 2 includes a target position setting step S31, first calculation steps S32 and S33, second calculation steps S34 to S36, and a third calculation step S37, as shown in Fig. 10. The first calculation step, second calculation step, and third calculation step may be performed separately or collectively.

[0081] (1) Target position setting step S31 First, a target position is set so that at least the contact portion 12 comes into contact with the measurement object O. The target position Xd is set so as to move downward in FIG.

[0082] (2) First calculation step S32~S33 Next, the contact portion 12 is moved toward the target position, and a first contact portion position X1 (see FIG. 9) is detected, which is the position of the contact portion 12 when the contact portion 12 is in contact with the measurement object O (see step S32 in FIG. 10). Then, a first difference, which is the difference between the contact portion position X1 when the contact portion 12 is in contact with the measurement object O and the target position Xd1, and a first external force F1 generated on the contact portion 12, which is calculated based on the first difference, are calculated (see step S33 in FIG. 10).

[0083] (3) Second calculation step S34~S36 Next, by moving the target position Xd1 to the target position Xd2 (see step S34 in FIG. 10), the contact portion position becomes X2 (see the lower diagram in FIG. 9), and a second difference different from the first difference is calculated. Then, a second external force F2 generated at the contact portion 12 is calculated based on the second difference (see steps S35 and S36 in FIG. 10).

[0084] (4) Third calculation step S37 Then, the hardness of the measurement object is calculated based on the first difference, the first external force, the second difference, and the second external force (see step S37 in FIG. 10).

[0085] In this way, the hardness of the measurement object O can be calculated.

[0086] <Measurement program according to the third embodiment> Next, a description will be given of a measurement program according to embodiment 3. The measurement program according to embodiment 3 causes a CPU to execute a target position setting process, a first calculation process, a second calculation process, and a third calculation process, and measures the hardness of a measurement object O.

[0087] (1) Target position setting process First, the target position Xd is set so that at least the contact portion 12 comes into contact with the measurement object O (see step S31 in FIG. 10).

[0088] (2) First calculation process Next, the contact portion 12 is moved toward the target position Xd1 to detect a first contact portion position X1 (see FIG. 9), which is the position of the contact portion 12 when the contact portion 12 is in contact with the measurement object O. Then, a first difference, which is the difference between the contact portion position X1 when the contact portion 12 is in contact with the measurement object O and the target position Xd1, and a first external force F1 generated on the contact portion 12, which is calculated based on the first difference, are calculated (see steps S32 and S33 in FIG. 10).

[0089] (3) Second arithmetic processing Next, the contact portion 12 is further moved toward the target position (see step S34 in FIG. 10), and a second contact portion position X2 (see the lower diagram in FIG. 9), which is the position of the contact portion 12 when it is moved, is detected, and a second difference and a second external force F2 generated on the contact portion 12, which is calculated based on the second difference, are calculated (see steps S35 and S36 in FIG. 10).

[0090] (4) Third arithmetic processing Next, the hardness of the measurement object O is calculated based on the first difference, the first external force, the second difference, and the second external force (see step S37 in FIG. 10).

[0091] As described above, the measuring device, measuring method, and program according to embodiment 3 differ from the measuring device according to embodiment 2 in that they perform hardness measurement instead of dimensional measurement, but like the measuring device, measuring method, and program according to embodiment 2, the control unit 30 has a calculation unit 31 that measures a predetermined physical quantity based on the external force F generated at the contact portion 12, which is calculated based on the difference between the set target position Xd and the contact portion position, so that the physical quantity of the object to be measured can be calculated simply by detecting the set target position Xd and the contact portion position. Therefore, a dedicated measuring instrument is not required, and there is no need to move the object to be measured to the dedicated measuring instrument using a manipulator or the like, thereby improving work efficiency.

[0092] According to the measuring device of embodiment 3, hardness measurement can be performed simply by changing the control of the control unit without changing the device configuration from the measuring device 1 of embodiment 1 and the measuring device of embodiment 2. Therefore, it can be easily switched from mass measurement and dimension measurement.

[0093] The measuring device, measuring method, and program according to embodiment 3 have the same configuration as the measuring device, measuring method, and program according to embodiment 2, except that they perform hardness measurement instead of dimensional measurement, and therefore have the corresponding effects of the measuring device, measuring method, and program according to embodiment 2.

[0094] [Variation 3] The measurement device according to Modification 3 basically has the same configuration as the measurement device according to Embodiment 2, but differs from the measurement device according to Embodiment 2 in that it performs shape measurement. That is, in the measurement device according to Modification 3, the control unit 30 moves the contact unit 12 along the outer edge of the object to be measured, and the calculation unit 31 measures the dimensions of the object to be measured at each position along the outer edge of the object to be measured based on a preset threshold value and an external force, thereby measuring the shape of the object to be measured.

[0095] For example, a contact portion 12d provided with rollers (or wheels) is moved along the outer edge of the object to be measured (moved from the state indicated by the dashed line to the state indicated by the solid line in FIG. 11). Then, at each position along the outer edge of the object to be measured, the dimensions of the object to be measured are measured based on a preset threshold value and the external force (see embodiment 2 for the method of dimension measurement). This makes it possible to measure the shape of the object to be measured. Note that the target position may be freely determined, but in FIG. 11, it is set to move along the outer shape of the object to be measured.

[0096] As described above, the measuring device according to Modification 3 differs from the measuring device according to Embodiment 2 in that it performs shape measurement, but like the measuring device according to Embodiment 2, the control unit 30 has a calculation unit 31 that measures a predetermined physical quantity based on the external force F generated at the contact portion 12, which is calculated based on the difference between the set target position Xd and the contact portion position, so that the physical quantity of the object to be measured can be calculated simply by detecting the set target position Xd and the contact portion position. Therefore, a dedicated measuring instrument is not required, and there is no need to move the object to be measured to the dedicated measuring instrument using a manipulator or the like, thereby improving work efficiency.

[0097] Although the present invention has been described above based on the above embodiment, the present invention is not limited to the above embodiment and can be embodied in various forms without departing from the spirit of the present invention, and for example, the following modifications are also possible.

[0098] (1) The positions, sizes, lengths, etc. described in the above embodiments (including each modified example; the same applies below) are examples and can be changed within the scope that does not impair the effects of the present invention.

[0099] (2) In the above embodiments, the contact portion is moved using a manipulator, but the present invention is not limited to this. Any appropriate configuration that can move the contact portion and detect the position of the contact portion may be used.

[0100] (3) In the above embodiments, the position of the contact portion is detected using an encoder, but the present invention is not limited to this. The position of the contact portion may be detected using a sensor or by any other appropriate method.

[0101] (4) In each of the above embodiments, the control unit may operate the contact unit while controlling the impedance. This configuration allows the contact unit to perform various tasks, and allows mass, dimension, and hardness measurements to be performed between tasks, resulting in the advantage of being able to perform tasks and measurements with high work efficiency. [Explanation of symbols]

[0102] 1, 1a, 2, 2a, 3, 3a, 4...measuring device, 10...manipulator, 12, 12b, 12c, 12d...contact portion, 20...position detection portion, 30...control portion, 31...calculation portion, 100...computer, 105...CPU, O...measurement object, X1...first contact portion position, X2...second contact portion position, Xd...target position

Claims

1. A measuring device that detects a contact position, which is the position of the contact part before and after the contact part grips a measurement object or the measurement object is placed on the contact part, and measures the mass of the measurement object as a physical quantity, comprising: the contact portion configured to be able to come into contact with the measurement object; a position detection unit that detects the contact position, which is the position of the contact portion; a control unit including a target position information generation unit that sets a target position, and a calculation unit that measures a mass of the measurement object based on an external force generated at the contact portion, the external force being calculated based on a difference between the target position set by the target position information generation unit and the contact portion position, the position detection unit detects a first contact position, which is a position of the contact unit before the contact unit grips the object to be measured or before the object to be measured is placed on the contact unit, and detects a second contact position, which is a position of the contact unit after the contact unit grips the object to be measured or after the object to be measured is placed on the contact unit; the calculation unit measures a first external force calculated based on a difference between the target position and the first contact position, a second external force calculated based on a difference between the target position and the second contact position, and a mass of the measurement object based on a relationship between the external forces and gravity applied to the measurement object; The measuring device according to claim 1, wherein the target position information generating unit sets the target position to a fixed position during the period from when the first contact position is detected to when the second contact position is detected.

2. A measurement device that measures a physical quantity of a measurement object, a contact portion configured to be able to come into contact with the measurement object; a position detection unit that detects a contact position, which is the position of the contact portion; a control unit having a calculation unit that measures a physical quantity of the measurement object based on an external force generated at the contact portion, the external force being calculated based on a difference between a set target position and the contact portion position, the control unit sets the target position so that at least the contact unit contacts the measurement object, and moves the contact unit toward the target position; The measuring device is characterized in that the calculation unit measures the dimensions of the measurement object based on a preset threshold value and the external force.

3. A measurement device that measures a physical quantity of a measurement object, a contact portion configured to be able to come into contact with the measurement object; a position detection unit that detects a contact position, which is the position of the contact portion; a control unit having a calculation unit that measures a physical quantity of the measurement object based on an external force generated at the contact portion, the external force being calculated based on a difference between a set target position and the contact portion position, the control unit sets the target position so that at least the contact unit contacts the measurement object, and moves the contact unit toward the target position; The calculation unit a first difference that is the difference when the contact portion is in contact with the measurement object, and a first external force that is generated at the contact portion and that is calculated based on the first difference; A measuring device characterized by measuring the hardness of the object to be measured based on a second difference different from the first difference and a second external force generated at the contact portion calculated based on the second difference.

4. A measurement device that measures a physical quantity of a measurement object, a contact portion configured to be able to come into contact with the measurement object; a position detection unit that detects a contact position, which is the position of the contact portion; a control unit having a calculation unit that measures a physical quantity of the measurement object based on an external force generated at the contact portion, the external force being calculated based on a difference between a set target position and the contact portion position, the control unit moves the contact unit along an outer edge of the measurement object, The calculation unit measures the shape of the object to be measured by measuring the dimensions of the object to be measured based on a predetermined threshold value and the external force at each position along the outer edge of the object to be measured.

5. 5. The measurement device according to claim 1, wherein the external force is calculated based on the following formula (1): where M is an inertia matrix, D is a viscosity matrix, K is a stiffness matrix, F is an external force vector as the external force, X is a position and orientation vector of the contact part as the contact part position, and Xd is a target position and orientation vector as the target position. [Equation 1]

6. further comprising a robot arm for controlling the contact portion; The measuring device according to any one of claims 1 to 4, characterized in that the control unit moves the contact portion toward the target position by controlling the rotational torque of a motor provided on the axis of the robot arm.

7. Further, a movable part that moves the contact part is provided, 5. The measuring device according to claim 1, wherein the control unit performs impedance control on the movable unit and measures a predetermined physical quantity of the object to be measured.

8. a contact portion position detecting step of detecting the position of a contact portion configured to be able to come into contact with the measurement object; a calculation step of measuring a physical quantity of the object to be measured based on an external force generated at the contact portion, the external force being calculated based on a difference between a set target position and a position of the contact portion, a first contact portion position detecting step of detecting a first contact portion position, which is a position of the contact portion before the contact portion grips the measurement object or before the measurement object is placed on the contact portion; a step of gripping the object to be measured with the contact portion or placing the object to be measured on the contact portion; a second contact portion position detecting step of detecting a second contact portion position, which is a position of the contact portion after the contact portion has gripped the measurement object or after the measurement object has been placed on the contact portion; a calculation step of calculating a first external force calculated based on a difference between the target position and the first contact position, a second external force calculated based on a difference between the target position and the second contact position, and measuring a mass of the object to be measured based on a relationship between the external forces and gravity applied to the object to be measured, A measuring method, characterized in that the target position is set at a fixed position during the period from the first contact position detection step to the second contact position detection step.

9. a contact portion position detecting step of detecting the position of a contact portion configured to be able to come into contact with the measurement object; a calculation step of measuring a physical quantity of the object to be measured based on an external force generated at the contact portion, the external force being calculated based on a difference between a set target position and a position of the contact portion, a target position setting step of setting the target position so that at least the contact portion comes into contact with the measurement object; a contact portion position detecting step of moving the contact portion toward the target position and detecting a contact portion position that is a position of the contact portion; A measurement method comprising the calculation step of measuring the dimensions of the object to be measured based on the external force calculated based on the contact position and a preset threshold value.

10. 10. The measurement method according to claim 9, wherein the target position setting step sets the target position so as to move in a direction away from the contact portion.

11. a contact portion position detecting step of detecting the position of a contact portion configured to be able to come into contact with the measurement object; a calculation step of measuring a physical quantity of the object to be measured based on an external force generated at the contact portion, the external force being calculated based on a difference between a set target position and a position of the contact portion, a target position setting step of setting the target position so that at least the contact portion comes into contact with the measurement object; a first calculation step of moving the contact portion toward the target position, detecting a first contact portion position that is a position of the contact portion when the contact portion is in contact with the measurement object, and calculating a first difference that is the difference at the first contact portion position and a first external force generated in the contact portion that is calculated based on the first difference; a second calculation step of detecting a second contact position, which is a position of the contact portion when the contact portion is further moved toward the target position, and calculating a second difference, which is the difference at the second contact position, and a second external force generated in the contact portion, which is calculated based on the second difference; and a third calculation step of calculating the hardness of the object to be measured based on the first difference, the first external force, the second difference, and the second external force.

12. a contact portion position information input process for inputting contact portion position information relating to the position of a contact portion configured to be able to come into contact with the measurement object; a measurement program for causing a CPU to execute a calculation process for calculating a physical quantity of the measurement object based on an external force generated at the contact portion, the external force being calculated based on a difference between a set target position and a position of the contact portion, and measuring the physical quantity of the measurement object, a first contact portion position information input process for inputting first contact portion position information relating to a first contact portion position, which is a position of the contact portion before the contact portion grips the measurement object or before the measurement object is placed on the contact portion; a second contact portion position information input process for inputting second contact portion position information relating to a second contact portion position, which is a position of the contact portion after the contact portion has gripped the measurement object or after the measurement object has been placed on the contact portion; a measurement program that causes a CPU to execute a calculation process to calculate a mass of the measurement object based on a relationship between a first external force calculated based on a difference between the target position and the first contact position, a second external force calculated based on a difference between the target position and the second contact position, and gravity applied to the measurement object, A measurement program characterized in that the target position is set to a fixed position from before the contact portion grasps the object to be measured or before the object to be measured is placed on the contact portion to after the contact portion grasps the object to be measured or after the object to be measured is placed on the contact portion.

13. a contact portion position information input process for inputting contact portion position information relating to the position of a contact portion configured to be able to come into contact with the measurement object; a measurement program for causing a CPU to execute a calculation process for calculating a physical quantity of the measurement object based on an external force generated at the contact portion, the external force being calculated based on a difference between a set target position and a position of the contact portion, and measuring the physical quantity of the measurement object, a target position setting process for setting the target position so that at least the contact portion comes into contact with the measurement object; a contact portion position information input process for moving the contact portion toward the target position and inputting contact portion position information relating to a contact portion position that is a position of the contact portion; A measurement program characterized by causing a CPU to execute the calculation process of calculating the external force calculated based on the contact position and the dimensions of the object to be measured based on a preset threshold value.

14. a contact portion position information input process for inputting contact portion position information relating to the position of a contact portion configured to be able to come into contact with the measurement object; a measurement program for causing a CPU to execute a calculation process for calculating a physical quantity of the measurement object based on an external force generated at the contact portion, the external force being calculated based on a difference between a set target position and a position of the contact portion, and measuring the physical quantity of the measurement object, a target position setting process for setting the target position so that at least the contact portion comes into contact with the measurement object; a first calculation process of moving the contact portion toward the target position, detecting a first contact portion position that is a position of the contact portion when the contact portion is in contact with the measurement object, and calculating a first difference that is the difference at the first contact portion position, and a first external force generated in the contact portion that is calculated based on the first difference; a second calculation process of detecting a second contact position, which is a position of the contact portion when the contact portion is further moved toward the target position, and calculating a second difference, which is a difference at the second contact position, and a second external force generated in the contact portion, calculated based on the second difference; and a third calculation process for calculating the hardness of the object to be measured based on the first difference, the first external force, the second difference, and the second external force.

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